Windmill



Dec. 27, 1927. 1,654,436 C. W. SNQOK wmDMI-Lp Filed April 6. 1925 Patented Dec. 27, '1927.

"UNITED STATES PATENT, OFFICE.

WIN DMILL.

Application filed April 6, 1925, Serial No. 21,176, and in Australia. September 9, 1924.

The object of this invention is to provide means whereby air suctional action is set up and maintained at the rear of the blades consequently facilitating the rotation of the mill wheel, more particularly when a low pressure breeze is blowing thus avoiding any back pressure of the wind against the rear surfaces of the blades.

This object is attained by forming the blades or sails of the mill of hollow section and whose front and rear surfaces are of different curvatures-said blades being tapered both in longitudinal and transverse sections. The object is further attained by the use of a cap either of semi-circular or conical section which extends outwardly from the face of the mill and fills up the central open or partly open space hitherto existing in windmills and diverts the wind on to the front surfaces of the blades in order that they will be subject to the maximum force and influence of the wind.

Furthermore the object is attained in providing a streamline surface which extends rearwardly from the gear casing to the tail i of the mill. The wind as it leaves the blades is freely guided from the mill by the streamline surface consequently establishing an air suctional action and further assisting the mill in its rotation.

By means of this above described structure it will be seen that the mill is rendered easy of Working in a light breeze as the wind is effectively led on to the front face of the blades then after performing its duty is led away from the mill. without causing any back suctional action which would otherwise retard the mill in its working.

In order that the invention may be clearly understood reference will. be made to the attached drawings wherein Fig. 1 is a part side elevation. shmving a streamline construction of the casing and tail of the milltwo broken blades only being shown for sake of olearness. Fig. 2 is a plan view of sameone blade being shown in full. Fig. 3 is a front face view of Fig. 2, one blade only being shown. Fig. 4 is a perspective view partly in section of a blade made in accord with this invention.

Referring to said drawings, a is a windmill. driving blade of hollowsection having its front surface I) of a differenticurva ture or radius to that of its rear surface as c-said blade being tapered in longitudinal and transverse section as seen clearly in Fig. 4.

By reason of the peculiar construction of the blades (4 an air suctional action is set up and maintained in respect therewith consequently facilitating the rotation of the mill and thereby utilizing the maximum effort andinfluence of a low pressure wind and furthermore nullifying any back pressure of the wind against the rear surfaces of the blades thus removing a hitherto disability or retardation in the working on Windmills. In order to lead and divert the wind on to the front surfaces 6 of the blades a cap as d preferably of semicircular section is fitted at a central and frontward position on the mill wheel frame e in order that it will fill up the open or partly open central space between the inner terminals of the blades asaid cap is secured in position by nut 7" to the main shaft 9 of the mill and also by brackets j to the radial stays 7c of the mill wheel frame esai-d cap formed with slots m to admit of the therethrough placement of said stays 7a.

This cap 0! makes close fitting and rotatable contact against the gear casing n of the mill as seen in Figs. 1 and 2. Extending rearwardly from said gear casng a is positioned the tail 7) of the mill said tail being of a streamline format-ion and whose contour gently leads from said gear casing '22. This tail is of the formation as seen in Figs. 1 and 2, having the frontwardly inclined portion r whereat by hinge s it is secured to the gear casing n and provided with a rubber buffer t which acts as a shock absorbing agent in respect of the gear casingsaid tail is also provided with a spring y whose purpose is to return the tail to the normal position when it is necessary that "the mill should be brought into the wind.

What I claim as my invention and desire to secure by Letters Patent is In a windmill construction of the class specified, the combination of a rotatable frame having inner and outer circular concentrically arranged frame members with a centrally located cap within the inner frame member, the cap having radial slots extending outwardly through the periphery there-v of, a main shaft on Which said frame and cap are mounted, a gear casing cooperating With the shaft and from which the said cap extends outwardly, radially arranged blades secured to the frame, the said frame having radial stays, the cap adapted to fill the space between the inner terminals of the blades and having the stays fitted in the slots thereof, the cap being secured to the radial stays by brackets attached to the inner frame member, and a tail vane secured to the gear casing.

In testimony whereof I have hereunto set my hand. 7

' CHARLES WILLIAM SNOOK. 

